Objective.Hypertensive disorders represent the most common complications of human pregnancy with substantial impact on fetal and maternal outcomes. Inositol phosphoglycan P-type has recently been identified as a novel marker of preeclampsia, the most severe form of hypertension during pregnancy, with a significant increase in urinary excretion preceding the clinical diagnosis. Methods.A prospective, longitudinal study was carried out to assess the potential of urinary levels of inositol phosphoglycan P-type as a screening test for preeclampsia. A specific ELISA-based test was used to assess urinary levels of P-IPG. Results.Nine patients out of 93 women recruited (496 urinary samples were collected) went on to develop preeclampsia in a cohort of women with high-risk pregnancies. A cut-off value of urinary inositol phosphoglycan P-type was identified by ROC analysis providing a sensitivity and specificity for the current protocol of 88.9% and 62.7%, respectively. Twenty-three women with healthy pregnancies had sporadic episodes of increased excretion of inositol phosphoglycan P-type during pregnancy that consistently resolved back to normal baseline without development of preeclampsia. There was no correlation of urine levels of inositol phosphoglycan P-type and urine protein and patients with gestational hypertension had normal levels of urine inositol phosphoglycan P-type. Conclusions.These findings suggest that, given the rapid raise of P-IPG before the onset of the disease, multiple assessments may help at identifying women at risk of developing preeclampsia.